1. Field of the Invention
The present invention relates to an automatic transmission mechanism preferably employed for an automobile or the like and more particularly relates to an automatic transmission mechanism with a plurality of spindle-shaped frictional clutch members disposed in a clutch holder which is adapted to be axially displaced in dependence on a torque load from a driven shaft.
2. Description of the Prior Art
The conventional transmission mechanism is constructed such that gear changing is effected between both driving and driven gear assemblies by manually or automatically displacing or shifting an intermediate gear or gears with the aid of a suitable control lever mechanism, for instance, when starting running of an automobile or going up a hill. Specifically, when starting running, gear changing is effected by way of a low gear, a second gear, a third gear and finally a top gear. Further, when going up a hill, gear changing is returned to the third gear or the second gear, whereas when going up a steep hill, gear changing is returned further to the low gear by way of the second gear. On the other hand, when the car runs on level road again, the gear changing mechanism is shifted back to the top gear. During gear changing with the conventional transmission mechanism it is usually necessary to turn off a clutch mechanism. As is well known, the conventional transmission mechanism is very complicated in structure and thereby is manufactured at an expensive cost.